The present invention relates to the field of combustion engines, more specifically to a piston assembly for an internal combustion diesel engine having a piston diameter of 160 to 650 mm, the piston assembly comprising a top part and a body part and a gudgeon pin connectable to each other,                the top part defining, when installed in a cylinder of the engine, the piston side of a combustion chamber, and        the body part having an aperture for a gudgeon pin, bosses for distributing forces, when in use, between the piston and the gudgeon pin, the body part having an interior, an outer surface and operable connecting surfaces,        the gudgeon pin for connecting the piston to a connecting rod of the engine in a pivotal manner.        
One aspect of the invention relates to the gudgeon pin for use in the piston assembly.